Acrylic Atomic Gray Thermalene Food Server Dish, 1960s Vintage

Rectangular 3 part buffet server in smoke gray and white plastic. The bottom section is for ice to keep food items in the white plastic section cold. Unmarked. Some fine scratching and one bigger scratch on the lid, see photos. 

It measures 10" by 6 3/4" and is about 7" tall. The white section holds just under 4 cups.